The present disclosure relates to an audio signal processing apparatus and an audio signal processing method that perform correction processing on audio signals to correct speaker characteristics.
In devices that perform audio signal processing, such as acoustic devices (hereinafter, referred to as audio signal processing devices), there are techniques in which correction processing such as digital filter processing is performed on an audio signal acquired from a sound source. The audio signal processing device outputs an audio signal that has been subjected to correction processing from a speaker or the like, thus being capable of improving a sound quality of the audio output from the speaker or the like, acoustic effects, or the like.
Examples of such correction processing include correction of “speaker characteristics”. The speaker characteristics refer to frequency characteristics of a speaker, which differ depending on a bore or the like of a speaker or an internal structure thereof. Here, the frequency characteristics refer to phase characteristics as deviation in time between phases of an audio signal input to the speaker and an audio signal output from the speaker, amplitude characteristics as an intensity ratio, or the like.
Examples of the audio signal processing device capable of correcting speaker characteristics by performing correction processing on an audio signal include a “signal processing apparatus” disclosed in Japanese Patent Application Laid-open No. 2009-55079 (paragraph [0034], FIG. 1; hereinafter, referred to as Patent Document 1), for example. This signal processing apparatus is intended to improve low-level components of a compact speaker by combining amplification of a low-frequency band signal of an input audio signal and its shift to a high frequency band.